"A machine can decrease either the input force or the input distance needed to do a given amount of work" is the best statement that describes why a machine is useful.
Answer: Option D
<u>Explanation
:</u>
A machine is simply defined as a device that helps humans, helping them to transfer the required amount of force to compete any task, changing the direction of motion, increasing the magnitude of force to complete any task, reduce the time or distance needed to cover while performing any task.
Machines can be simple mechanical device or a combination of multiple mechanical or technical devices to reduce the amount of input force or increase the output.
Answer:
B.Metal B has higher density than metal A
D: is the anwser that your looking for
Answer:
A. SrSO4
Explanation:
it is insoluble in water therefore it is the precipitate formed in the reaction
Mass number is
protons + nuetrons
So,
7 + 8 = 15
——-
Atomic number is the number of protons
so,
7
